Parametric optimization of wire electro discharge machining of Inconel 718 using Taguchi’s methodology

Abstract

Abstract In this demanding world of advanced technologies, the Wire Electro Discharge Machining (WEDM) has evolved as one of the promising methods for efficient machining of advanced materials (super alloys, ceramics and composites). WEDM, an important advanced machining process meets the demands of precise complex geometry and effective stock removal. The work material chosen for the present study is Nickel based age-hardenable austenitic super alloy Inconel 718, having high strength, better oxidation-corrosion resistance, and high temperature resistance. Inconel 718 finds widespread application in aerospace, marine, automobile industries, nuclear power, and oilfield applications. The present study deals with the experimental analysis and parametric optimization of slitting Inconel 718 with brass wire using WEDM. The objective of the proposed work is to optimize the process parameters namely Pulse-on time (TON), Open Circuit Voltage (OV), Wire Tension (WT) and Wire Feed Rate (WFR). The required experiments were conducted using Taguchi’s Orthogonal Array [L9 (34)] to predict optimal parametric settings for the responses namely Surface Roughness (SR) and Material Removal Rate (MRR). The results of ANOVA show that TON has highest influence on MRR followed by OV, WFR and WT. TON has highest influence on SR followed by WFR, WT and OV. When OV or TON increases then MRR also increases. When TON or OV or WFR decreases then SR also decreases. The optimal parameter for MRR is OV-60 V, TON-0.75 µs, WFR-1 m/min, WT-1700 g and for SR is OV-50 V, TON-0.25 µs, WFR-1 m/min and WT-1100 g.